U.S. patent application number 11/106280 was filed with the patent office on 2006-10-19 for methods and apparatus to reduce heat transfer from fluids in conduits.
This patent application is currently assigned to Halliburton Energy Services, Inc.. Invention is credited to Dale E. Jamison.
Application Number | 20060231150 11/106280 |
Document ID | / |
Family ID | 36607532 |
Filed Date | 2006-10-19 |
United States Patent
Application |
20060231150 |
Kind Code |
A1 |
Jamison; Dale E. |
October 19, 2006 |
Methods and apparatus to reduce heat transfer from fluids in
conduits
Abstract
Methods and apparatus are provided for reducing heat transfer to
or from a fluid contained within double-walled conduit. A method
for reducing the heat transfer from a fluid contained within
double-walled conduit includes providing an inner conduit, the
inner conduit substantially containing the fluid; providing an
outer conduit, the outer conduit substantially surrounding the
inner conduit; and connecting the inner conduit to the outer
conduit via at least one elongated conduction pathway so as to
reduce the heat transfer from the fluid.
Inventors: |
Jamison; Dale E.; (Humble,
TX) |
Correspondence
Address: |
CRAIG W. RODDY;HALLIBURTON ENERGY SERVICES
P.O. BOX 1431
DUNCAN
OK
73536-0440
US
|
Assignee: |
Halliburton Energy Services,
Inc.
|
Family ID: |
36607532 |
Appl. No.: |
11/106280 |
Filed: |
April 14, 2005 |
Current U.S.
Class: |
138/114 ;
138/112; 138/113; 138/148 |
Current CPC
Class: |
F16L 59/065 20130101;
F16L 59/143 20130101 |
Class at
Publication: |
138/114 ;
138/112; 138/113; 138/148 |
International
Class: |
F16L 9/18 20060101
F16L009/18 |
Claims
1. A method of reducing heat transfer from a fluid in a hydrocarbon
production conduit system comprising: providing an inner conduit,
the inner conduit substantially containing the fluid; providing an
outer conduit, the outer conduit substantially surrounding the
inner conduit; and connecting the inner conduit to the outer
conduit via at least one elongated conduction pathway so as to
reduce the heat transfer from the fluid in the hydrocarbon
production conduit system, the elongated conduction pathway not
including a conduction path traversing a shortest distance between
the inner conduit and the outer conduit.
2. The method of claim 1 wherein the inner conduit is a pipe; and
wherein the outer conduit is a pipe.
3. The method of claim 1 wherein the elongated conduction pathway
is formed by positioning at least a portion of the elongated
conduction pathway at an angle oblique to the walls of the
conduits.
4. The method of claim 1 wherein the elongated conduction pathway
is formed by positioning at least a portion of the elongated
conduction pathway directed away from the perpendicular of the
walls of the conduits.
5. (canceled)
6. The method of claim 1 wherein the outer conduit forms part of a
hydrocarbon production piping system.
7. The method of claim 1 wherein the outer conduit has a threaded
connection at one end of the outer conduit for mating with another
section of conduit.
8. The method of claim 1 wherein at least one end of the inner
conduit is adapted to form a metal to metal seal with another
section of conduit.
9. The method of claim 1 wherein at least one end of the inner
conduit comprises an elastomeric seal for forming a seal with
another section of conduit.
10. The method of claim 1 ftrther comprising an additional conduit
substantially surrounding the outer conduit.
11. The method of claim 1 wherein the connecting of the inner
conduit to the outer conduit is made via at least two elongated
conduction pathways so as to form an enclosed space circumscribed
by the intersection of the at least two conduction pathways, the
inner conduit and the outer conduit; and providing at least one
port traversing the outer conduit.
12. The method of claim 11 further comprising providing at least
one additional port traversing the outer conduit to the enclosed
space.
13. The method of claim 11 further comprising pulling a vacuum on
the enclosed space.
14. A deepwater hydrocarbon production piping system for reducing
heat loss from a contained fluid comprising: a pipe segment, the
pipe segment comprising an inner pipe; an outer pipe, the outer
pipe substantially surrounding the inner pipe; and at least one
elongated conduction pathway connecting the inner pipe to the outer
pipe, the elongated conduction pathway not including a conduction
path traversing a shortest distance between the inner pipe and the
outer pipe; and a plurality of pipe segments joined longitudinally
to form a deepwater hydrocarbon production piping system.
15. A pipe apparatus comprising: an inner pipe; an outer pipe, the
outer pipe substantially surrounding the inner pipe; and at least
one elongated conduction pathway connecting the inner pipe to the
outer pipe, the elongated conduction pathway not including a
conduction path traversing a shortest distance between the inner
pipe and the outer pipe so as to reduce the heat transfer from a
fluid to an external environment.
16. The pipe apparatus of claim 15 wherein the elongated conduction
pathway is longer than the length traversed by a straight line
between the inner pipe and the outer pipe.
17. The pipe apparatus of claim 15 wherein the outer pipe has a
threaded connection at one end of the outer pipe for mating with
another section of pipe.
18. The pipe apparatus of claim 15 further comprising a means for
attaching the inner pipe to the outer pipe and for reducing thermal
conductivity between the pipes.
19. The pipe apparatus of claim 15 wherein at least one end of the
inner pipe is adapted to form a seal with another pipe
apparatus.
20. (canceled)
21. The deepwater hydrocarbon production piping system of claim 14
wherein the connecting of the inner conduit to the outer conduit is
made via at least two elongated conduction pathways so as to form
an enclosed space circumscribed by the intersection of the at least
two conduction pathways, the inner conduit and the outer conduit
and further comprising at least one additional port traversing the
outer conduit to the enclosed space.
22. The deepwater hydrocarbon production piping system of claim 14
further comprising a means for attaching the inner pipe to the
outer pipe and for reducing thermal conductivity between the pipes.
Description
BACKGROUND
[0001] The present invention relates to heat transfer applications,
and more particularly, to methods and apparatus for reducing
conduit-related heat transfer.
[0002] Fluids transported through long lengths of conduit can lose
significant amounts of heat to the environment. This heat loss may
be particularly problematic when a significant temperature
differential exists between the transported fluid and its
environment. One example of such a situation may be the flowing of
a fluid through deepwater production piping from a deepwater oil
and gas well to an oil and gas platform at the water surface. In
such an example, a fluid may be transported long distances through
deepwater production piping, typically anywhere from 600 ft to
8,000 ft. In some cases, the transported fluid may be significantly
hotter than the temperature of its surrounding environment, in this
case, the ocean water. In some cases, the ocean water can be as
cold as -2.degree. C.
[0003] Deepwater production pipe is often double-walled pipe,
comprising an inner pipe and an outer pipe. These long pipes are
often constructed by longitudinally joining shorter segments of
pipe together to form longer lengths of pipe. The inner pipe may be
generally joined to the outer pipe at each segment of pipe via a
threaded connection or other suitable attachment means such as
welding. Often, the inner pipe may be insulated from the outer pipe
with an insulating material, an insulating fluid, or a vacuum. This
insulation between the inner and outer pipes is thought to reduce
the heat transfer from the fluid to the environment. Although this
insulation barrier often separates most of length of the inner pipe
from direct contact with the outer pipe, the inner pipe and outer
pipe are often in direct contact at the joints between the pipe
segments. This surface area of direct contact offers a more
conductive heat transfer path than the other insulated portions of
the pipe. Consequently, most of the heat loss from the fluid to the
environment occurs at this zone of contact between the inner and
outer pipe. Thus, one of the drawbacks of joining double-walled
conduit together in segmented intervals may be the short conductive
path formed between the inner and outer conduits at the joints of
each conduit segment as it may increase the amount of heat transfer
between the inner and outer conduits and therefore, the heat
transfer from the contained fluid.
[0004] Heat loss from a transported fluid to the environment may be
problematic for several reasons. In the case of deepwater
hydrocarbon production piping, for example, the cooling of a
transported fluid may cause crystallization or precipitation of
undesirable solids, such as asphaltine, paraffin, or hydrates. In
more severe cases, the recovered fluid may freeze or solidify in
the pipe due to heat loss to the external environment, which may,
in turn, pose further transportation difficulties with the
fluid.
[0005] Another problem may be the heating of a fluid by a warmer
environment. One example of such a situation is the transport of
cryogenic fluids. Because of the temperature differential between
cryogenic fluids and the surrounding environment, the heat transfer
from the environment to the cryogenic fluid can be substantial.
This heat transfer can be problematic for a variety of reasons,
including pressure buildup in the pipe or ice formation on the
pipe.
SUMMARY
[0006] The present invention relates to heat transfer applications,
and more particularly, to methods and apparatus for reducing
conduit-related heat transfer.
[0007] An example of a method of the present invention of reducing
heat transfer from a fluid comprises providing an inner conduit,
the inner conduit substantially containing the fluid; providing an
outer conduit, the outer conduit substantially surrounding the
inner conduit; and connecting the inner conduit to the outer
conduit via at least one elongated conduction pathway so as to
reduce the heat transfer from the fluid.
[0008] An example of the present invention of a deepwater oil and
gas production piping system for reducing heat loss from a
contained fluid comprises a pipe segment, the pipe segment
comprising an inner pipe; an outer pipe, the outer pipe
substantially surrounding the inner pipe; and at least one
elongated conduction pathway connecting the inner pipe to the outer
pipe; and a plurality of pipe segments joined longitudinally to
form a longer deepwater production piping system.
[0009] An example of a pipe apparatus of the present invention
comprises an inner pipe; an outer pipe, the outer pipe
substantially surrounding the inner pipe; and at least one
elongated conduction pathway connecting the inner pipe and to the
outer pipe so as to reduce the heat transfer from the fluid to the
external environment.
[0010] The features and advantages of the present invention will be
apparent to those skilled in the art. While numerous changes may be
made by those skilled in the art, such changes are within the
spirit of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] These drawings illustrate certain aspects of some of the
embodiments of the present invention and should not be used to
limit or define the invention.
[0012] FIG. 1 shows a cross-sectional view of a double-walled
conduit with inner and outer conduits connected via an elongated
conduction path in accordance with one embodiment of the present
invention.
[0013] FIG. 2 shows a cross-sectional view of a double-walled
conduit with inner and outer conduits connected via an elongated
conduction path having an optional port traversing the outer
conduit in accordance with one embodiment of the present
invention.
[0014] FIG. 3 shows a cross-sectional view of an apparatus
incorporating certain embodiments of the elongated conduction
path.
[0015] FIG. 4 illustrates a system with a deepwater production
piping coupled to an offshore platform and a deepwater oil and gas
well incorporating certain features of the present invention.
[0016] FIG. 5 illustrates a cross-sectional view of pipe segments
before being joined together in accordance with one embodiment of
the present invention.
DESCRIPTION
[0017] The present invention relates to heat transfer applications,
and more particularly, to methods and apparatus for reducing
conduit-related heat transfer.
[0018] The present invention provides methods and apparatus useful
in heat transfer applications. In particular, the methods and
apparatus of the present invention may be particularly useful in
reducing the heat transfer between a transported fluid and its
environment when the fluid is contained in a double-walled conduit.
By providing an elongated conduction path between the inner and
outer conduits, the heat transfer between a transported fluid and
its environment may be reduced. The term conduit, as used herein,
refers to any pipe, tube, or channel that may be adapted for the
transport of fluids.
[0019] FIG. 1 shows a cross-sectional view of a double-walled
conduit constructed of inner and outer conduits in accordance with
one embodiment of the present invention. An outer conduit 10 is
shown substantially surrounding an inner conduit 20. An elongated
conduction pathway 30 is shown connecting the inner conduit 20 to
the outer conduit 10.
[0020] In one embodiment, a fluid 40 may be provided substantially
contained in the inner conduit 20. The fluid 40 may be flowing
through the inner conduit 20. Occasionally, the fluid 40 may not be
flowing in the inner conduit 20 and may simply rest stationary,
possibly due to operational considerations.
[0021] An elongated conduction pathway 30 may conductively join the
inner conduit 20 and the outer conduit 10 in the vicinity of the
joints between the conduit segments. Further, the elongated
conduction pathway 30 may be formed by any geometric extension or
series of extensions of the conduction pathway between the inner
and outer conduits 10 and 20. This geometric extension may be any
extension or lengthening of at least a portion of the conduction
pathway directed away from the perpendicular of the surfaces of the
conduits 10 and 20. Stated otherwise, at least one elongated
conduction pathway may be longer than the length traversed by a
straight line between the inner and outer conduits. In certain
embodiments, a portion of the geometric extension may be at an
angle oblique to the planes formed by the surfaces of the conduits
10 and 20. The heat transfer through the conduit from the fluid may
be reduced, among other ways by extending the conduction pathway.
In many instances, this heat transfer may be a cooling of a warmer
fluid by a cooler external environment. In other instances,
however, the heat transfer may be a heating of a colder fluid by a
warmer environment.
[0022] The attachment of the elongated conduction pathway 30 to the
inner conduit 20 and to the outer conduit 10 may be by welding or
by any variety of methods known by one skilled in the art. Although
the connection depicted in FIG. 1 shows the elongated conduction
pathway 30 as the only connection between the inner and outer
conduits 10 and 20, other connections besides the elongated
conduction pathway 30 may be provided. Illustrative examples of
other types of connections include, but are not limited to, welds,
fasteners, adhesives, and other suitable coupling devices.
[0023] Additionally, insulation material may optionally be provided
between the inner and outer conduits 10 and 20. This insulation
material may reduce the heat transfer between the inner and outer
conduits along a substantial portion of the conduit segments.
[0024] The outer conduit 10 may substantially surround the inner
conduit 20 along most of the length of the conduits 10 and 20. In
certain embodiments, the outer conduit 10 may or may not surround
the inner conduit 20 in the vicinity of the joints between the
conduit segments. Thus, "substantially surrounding" as used herein
does not require that the outer conduit 20 surround the inner
conduit in the vicinity of the conduit segment joints. Further,
"substantially surrounding" does not require that the outer conduit
10 surround those portions of the inner conduit 20 where no outer
conduit 10 is present.
[0025] The inner and outer conduits 10 and 20 may be constructed of
any material that can withstand the pressures imposed upon them
during operation. Pressures on the conduits 10 and 20 may be caused
in part by the external environment, which in some cases may be
water, e.g., in an off-shore well situation, or by the fluid 40
contained in the inner conduit 20. In certain embodiments, the
conduits 10 and 20 may be constructed of any ceramic, plastic, or
metal including, but not limited to, stainless steel.
[0026] Although not depicted here, in certain embodiments, the
outer conduit may be further surrounded by another pipe or a
plurality of pipes to provide additional layers of heat transfer
resistance between the fluid and its environment.
[0027] FIG. 2 shows a cross-sectional view of a double-walled
conduit with inner and outer conduits 10 and 20 connected via an
elongated conduction path 30 having an optional port 60 traversing
the outer conduit 10 in accordance with one embodiment of the
present invention.
[0028] In certain embodiments, at least one optional port 60 may be
provided to pull a vacuum on an enclosed space circumscribed by the
elongated conduction pathways 30 and the inner and outer conduits
10 and 20. Alternatively, one or more ports 60 may be used to fill
the enclosed space with an insulating fluid 50. The insulating
fluid 50 may comprise any fluid with a low thermal conductivity.
Low thermal conductivity fluids include fluids with a thermal
conductivity below about 1 Btu/(hr ft .degree. F).
[0029] Further, the insulation fluid 50 may be a gelled or
viscosified insulation fluid. Gelling or viscosifying the
insulation fluid 50 may reduce any heat transfer due to convection
that might otherwise occur if the insulation fluid 50 were not
gelled or viscosified.
[0030] FIG. 3 shows a cross-sectional view of an apparatus
incorporating certain embodiments of the elongated conduction path
30. In particular, the elongated conduction pathway 30 may
conductively join the inner conduit 20 and the outer conduit 10 in
the vicinity of the joints between the conduit segments. Further,
the elongated conduction pathway 30 may be formed by any geometric
extension or series of extensions of the conduction pathway between
the inner and outer conduits 10 and 20. This geometric extension
may be any extension or lengthening of at least a portion of the
conduction pathway directed away from the perpendicular of the
surfaces of the conduits 10 and 20. Stated otherwise, at least one
elongated conduction pathway may be longer than the length
traversed by a straight line between the inner and outer conduits.
In certain embodiments, a portion of the geometric extension may be
at an angle oblique to the planes formed by the surfaces of the
conduits 10 and 20. Further, as shown in FIG. 3, a portion or
portions of the geometric extension of the conduction pathway may
be parallel to the surface of the conduits in addition to those
portion or portions of the geometric extension that are at an angle
oblique to the surface of the conduits.
[0031] Additionally, as one skilled in the art with the benefit of
this disclosure will appreciate, the elongated conduction pathway
may be separately provided via another member or members distinct
from the inner conduit and/or outer conduit. Alternatively, the
elongated conduction pathway may be formed by a lengthening of a
portion of the inner conduit and/or the outer conduit. Further,
although not depicted here, the elongated conduction pathways may
use bracing members to provide additional structural support to the
elongated conduction pathway. In certain embodiments, these bracing
members may comprise an insulating material.
[0032] FIG. 4 illustrates a system having a deepwater production
piping coupled to an offshore platform and a deepwater oil and gas
well incorporating certain features of the present invention.
[0033] In one embodiment, an oil and gas well 90 may be coupled to
the oil and gas deepwater production piping 70 which may in turn be
coupled to an offshore platform 80. The deepwater production piping
70 may be formed by longitudinally joining shorter segments of
conduit 70A-70G together. Although not depicted here, in certain
embodiments, the deepwater production piping 70 may extend below
the surface of the ground to reduce heat transfer between the fluid
and its surrounding environment.
[0034] FIG. 5 illustrates a cross-sectional view of pipe segments
before being joined together in accordance with one embodiment of
the present invention. Though the present invention may be
assembled in a variety of ways and sequences, this figure
illustrates one embodiment of the pipe segments before assembly in
the field. One end 15 of a portion of segmented pipe mates with
another end 17 of a segmented pipe. In this case, the outer conduit
of both ends 15 and 17 have threaded connections 19 which allow the
ends 15 and 17 to be coupled together. In these embodiments, a seal
is formed between segments of inner conduit via an an o-ring or
elastomeric seal 32. In further embodiments, the segments of inner
conduit may mate via an interference fit which forms a metal to
metal seal or other types of sealing methods known in the art may
be provided to further seal the union between the inner conduit
segments.
[0035] An example of a method of the present invention of reducing
heat transfer from a fluid comprises providing an inner conduit,
the inner conduit substantially containing the fluid; providing an
outer conduit, the outer conduit substantially surrounding the
inner conduit; and connecting the inner conduit to the outer
conduit via at least one elongated conduction pathway so as to
reduce the heat transfer from the fluid.
[0036] Therefore, the present invention is well adapted to attain
the ends and advantages mentioned as well as those that are
inherent therein. While numerous changes may be made by those
skilled in the art, such changes are encompassed within the spirit
of this invention as defined by the appended claims. The terms in
the claims have their plain, ordinary meaning unless otherwise
explicitly and clearly defined by the patentee.
* * * * *